package test1;

import java.util.Stack;

public class Test1 {
    public static void main(String[] args) {
        Stack<Integer> stack=new Stack<>();
        stack.push(1);
        stack.push(2);
        stack.push(3);
        stack.push(4);
        System.out.println(stack.pop());//4
        System.out.println(stack.peek());//3
        System.out.println(stack.peek());//3
        System.out.println(stack.empty());
        System.out.println("======");
        System.out.println(stack.isEmpty());
    }
}
